"At least a once a week I get a message from a young person ― as young as 11 ― who says they are ill and/or contemplating suicide because of the coming doomsday," NASA astrobiologist David Morrison is quoted as saying in the government's official response to the Armageddon rumor mill.

In fact, so heavy is the deluge of eschatological fear from letter-writing Americans that Morrison has taken it upon himself to be NASA's chief doomsday rumor debunker, setting up an entire page on NASA's official website devoted to addressing different doomsday scenarios.

Spoiler alert: None are expected to pan out.

"Many people don't know what they're afraid of," Morrison told NPR last week, "but they have heard this doomsday thing so often that they just come to me with a simple question: Will we have Christmas this year?"